Clamping attachment for t-squares.



P. W. KRAUSS.

GLAMPING ATTACHMENT FOB T-SQUARES. APPLICATION FILED JNE a, 1914.

1,121,512, Patented Dec. 15,1914.

'HE NoRRlS PETERS CoN FHn'm-l 'THU WASHINGTON, D, C

. PETER W; KRA'USS, OF SCRANTON,.PENNSYLVANIA, ASSIG-NOR T0 TECHNICAL SUPPLY CO., 0F SGRANTON, PENNSYLVANIA, A CORPORATION 0F NEW JERSEY.

CLAMPING ATTACHMENT FOR T-SQUARES. i

Specicatoniof Letters Patent.

Patented Dec. 15, 1.914.

. Airpiication mea June s, 1914. serial No. 842,736.

To all whom t may conccrnf Be it known that I,

Scranton, in the county of Lackawanna and State of Pennsylvania, have invented new and useful Vmprovements in Clamping Attachments for TSquares, of which the following is a specification. y

This invention relates to an improved clamping attachment for T-squares, proposing a device which will hold a. T-square against displacement from any desired position upon a drawing board but at the same time will permit the T-square to be readily and quickly adjusted from one positionto another.

The objects of the invention are to provide a device for the purpose stated, which maybe quickly and conveniently applied to any ordinary T-square and entails no modification of the construction of the T-square or of the drawing board; which reliably and certainly performs the function for which it is designed; which permits the ready re` Inoval of the T-square from` the drawing board and the readyl assemblage of the T- square upon the drawing board; yand which is readily adjustable along the blade of the T-square and permits of the ready adjustment of the T-squarev along the drawing board. i

Further objects of the invention are to provide an attachment for the purpose stated which shall be of an exceedingly simple structural nature; inexpensive to manufacture; readily manipulatable and comparatively small and inconspicuous.

An embodiment of the invention is illus-- tachment; Fig. L1 is a cross-sectional view of the attachment.

Similar characters of reference designate corresponding parts throughout the several views. v

The attachment is designed to be clamped upon the blade of the T-square and to take a bearing against the `adjacent face of the drawing board. For these purposes the at- PETER Krauss, l.a citizen of the United States,"residing at tachment includes essentially a clamping plate land a bearing plate 2. The plates land 2 are disposed at right angles to oney another, together having an L-shaped crosssection, and are preferably integrally joined', the plate 1 projecting from an edge, f

of the plate 2. In the drawings, the plate. 1 is shown as horizontally disposed and as projecting from the upper edge of the plate 2 which of course occupies a vertical plane. The plate 2 is formed immediately under the plate 1 with a slot 3 through` whichthe blade of the T-square upon which the attachment islitted projects, the length and width of this jslot being selected to enable the attachment to beused on'the larger as well as the smaller T-squares. Adjacent the lower edge ofthe slot 3 the plate 2 is provided with lugs or brackets 4 which are located immediately under the plate 1 in spaced parallel relation thereto and complement'the plate 1 to provide a clamp. The

plate 1 is provided with a clamping screw 5 which is preferably centrallylocated and at its lower end engages a leaf spring 6 which at one end is secured to an adjoining face of the plate 1 and adjacent the end face of said plate.l The provision of the spring 6 is preferred for the reasons that said spring prevents the blade of the T-square from being marred by the end of the screw, and furthermore, takes a relatively wide, uniform and strong. frictional bearing against said blade whereby to prevent accidental displacement of the attachment lengthwise of the blade but to permit thev ready adjustment' of the attachment to any position on the plate, whenever the occasion `may require, and without the manipulation of the screw 5.

The plate 2 is provided with a spring 7 which is preferably, as shown, secured at a point central thereof to said plate as at 8 'and has the portions at either side of its attached central portion 8 formed to provide spring bows which project beyond the lugs 2 and engage the adjacent face of the drawing board A.

rllhe device is fitted in position upon the blade of the T-square in the obvious manner and is moved .to a position against the adjoining face of the drawing board and while the device is being held with pressure to said face the screw 5 is turned downwardly so as to cause the spring 6 to engage the blade of the T-square with strong frictional pressure, sufficient to overcome or resist the tension of the spring 7 Should it be necessary to move the T-square along the drawing board, thisv is done in the usual manner by sliding the T-square to the position .desired against the resistance opposed by the spring 7, in consequence of its frictional engagement with the edge of the drawing board. Should it be desired to change the position of the attachment upon the bladel of the T-square, this is done by mo-ving the attachment lengthwise of the T-square against the resistance opposed by the spring 6 in consequence of its frictional engagement with the blade of the T-square. The T-square may bel readily removed from the drawing board and readily replaced, whenever the occasion may require, without any manipulation of the attachment. The blade of the T-square has a measure of springiness or resiliency, as is well known. A convenient way' of removing the T-square consists of pressing theplate 2 toward the adjoining edge of the board A so as to disengage the head of the T-squ'are from the opposite edge of said board, at which time the head of the T-square is sprung upwardly andthe square isv thus freed from its engagement with the board. Assuming that the proper adjustment of the attachment has been made, in order to apply the T-square to the board the operations described are reversed; that is to say, the plate 2 is pressed toward the adjoining edge of the board A andk the head ofthe T-square is depressed intoco-planar relation withV the board, at which time the pressure on the plate 2 is released and thespring 7 exercises its clamping function. y

The length of the slot 3 will, in most cases, begreater than the width of the blades of the T-squares ordinarily used. Byviitue of y this fact, the clamp may be used with swivelhead T-squares, which have their blades adl adjustmentof the device itself along thev blade of the T-square and the adjustment of the T-square along the drawing board entails vno manipulation of any parts.

Having fully described my invention, I claim l. A clamping attachment vfor T-squares comprising a clamping plate, bearing plate carrying the clamping plate and having a sloty immediately under the.` clamping plate through which the blade of the vT-l square may be inserted, a pair `of lugs carried-by the bearing plate and projecting y -under the clamping plate in parallel relation thereto adjacent the lower edge of the slot, a leaf spring carried bythe clamping plate to engage the blade of the T-square, 'a

screw for causing said spring to engage said" blade land resilientmeans carried by the bearing plate to engage the edge ofthe board upon which the T-square is positioned. e

2. A clamping attachment for T-squares comprising a clamping plate, a `bearing plate carrying the clampingv plate and having va slot immediately under the clamping plate through which the blade of the T'- square may be inserted, a pair of lugs carj ried by the bearing plate and projecting under the clamping plate in parallel relation thereto adjacent the lower edge of the slot, a leaf spring carried bythe clamping plate to engage the blade of the T-square, a screw for causing said spring to engage said blade and a leaf spring lcarried by the bearing plate to engage the edge `of the yboard upon'v which the T-square is positioned. y

3j. A clamping 'attachment for T -squares comprising a clamping plate,A a bearing plate, the clamping plate and the bearing.

plate together having an L-'shaped cross-section, the bearing'plate havingra slot immediately under the clamping plate through which the blade of the T-square maybe in-l. serted, clamping means carried` by the iool clamping platefto frictionally engage said i blade, and resilient means carried by the' bearino `ilate to enUaOe the board u on b C b which the "lsquare is mounted.

LA clamping attachment for "li-squares comprising a clamping plate, a 'bearing' plate, the clamping plate and the bearing platetogether having an L-shaped cross section, the bearing plate having a slot imme- Y diately under the clamping plate through which the blade ofv the T-square mayl be inserted, clamping means carried bythe clamping plate to frictionally engagel said,

blade, and a leaf spring carried by the bearing plate to engage the board'upon which the lT-square is mounted.

ln testimony whereof I have hereunto set y my hand in presence of two subscribing witnesses. j

PETER W. KRAUSS.

Witnesses:

C. F. WEICHEL, FRANK LAMBADER.

p Copies of this patent `may be obtained for five cents each, byladdressing 'thev Commissioner "of 2l?1`ateii1:s,j l

Washington, D.- C. 

